back up all your files, open the PC case, take out the hdd stick it in another box and wipe that baby clean. stick it back in the box and run the new version. all should be sweet to install, and vista, and all that comes with it will be gone. A secondary install on the drive or "upgrading" from vista will still leave traces of that abomination and your computer will always chug knowing it was tainted with that darkest moment of madness from M$...